|
public static TryReadBlock ( BinaryReader reader, long endExtraField, |
||
| reader | BinaryReader | |
| endExtraField | long | |
| field | ||
| return | bool | |
public static Zip64ExtraField GetJustZip64Block(Stream extraFieldStream, bool readUncompressedSize, bool readCompressedSize, bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64ExtraField;
ZipGenericExtraField zipGenericExtraField;
Zip64ExtraField zip64ExtraField1;
using (BinaryReader binaryReader = new BinaryReader(extraFieldStream))
{
while (ZipGenericExtraField.TryReadBlock(binaryReader, extraFieldStream.Length, out zipGenericExtraField))
{
if (!Zip64ExtraField.TryGetZip64BlockFromGenericExtraField(zipGenericExtraField, readUncompressedSize, readCompressedSize, readLocalHeaderOffset, readStartDiskNumber, out zip64ExtraField))
{
continue;
}
zip64ExtraField1 = zip64ExtraField;
return(zip64ExtraField1);
}
zip64ExtraField = new Zip64ExtraField()
{
_compressedSize = null,
_uncompressedSize = null,
_localHeaderOffset = null,
_startDiskNumber = null
};
return(zip64ExtraField);
}
return(zip64ExtraField1);
}
// There is a small chance that something very weird could happen here. The code calling into this function
// will ask for a value from the extra field if the field was masked with FF's. It's theoretically possible
// that a field was FF's legitimately, and the writer didn't decide to write the corresponding extra field.
// Also, at the same time, other fields were masked with FF's to indicate looking in the zip64 record.
// Then, the search for the zip64 record will fail because the expected size is wrong,
// and a nulled out Zip64ExtraField will be returned. Thus, even though there was Zip64 data,
// it will not be used. It is questionable whether this situation is possible to detect
// unlike the other functions that have try-pattern semantics, these functions always return a
// Zip64ExtraField. If a Zip64 extra field actually doesn't exist, all of the fields in the
// returned struct will be null
//
// If there are more than one Zip64 extra fields, we take the first one that has the expected size
//
public static Zip64ExtraField GetJustZip64Block(Stream extraFieldStream,
bool readUncompressedSize, bool readCompressedSize,
bool readLocalHeaderOffset, bool readStartDiskNumber)
{
Zip64ExtraField zip64Field;
using (BinaryReader reader = new BinaryReader(extraFieldStream))
{
ZipGenericExtraField currentExtraField;
while (ZipGenericExtraField.TryReadBlock(reader, extraFieldStream.Length, out currentExtraField))
{
if (TryGetZip64BlockFromGenericExtraField(currentExtraField, readUncompressedSize,
readCompressedSize, readLocalHeaderOffset, readStartDiskNumber, out zip64Field))
{
return(zip64Field);
}
}
}
zip64Field = new Zip64ExtraField();
zip64Field._compressedSize = null;
zip64Field._uncompressedSize = null;
zip64Field._localHeaderOffset = null;
zip64Field._startDiskNumber = null;
return(zip64Field);
}
public static List <ZipGenericExtraField> ParseExtraField(Stream extraFieldData)
{
ZipGenericExtraField zipGenericExtraField;
List <ZipGenericExtraField> zipGenericExtraFields = new List <ZipGenericExtraField>();
using (BinaryReader binaryReader = new BinaryReader(extraFieldData))
{
while (ZipGenericExtraField.TryReadBlock(binaryReader, extraFieldData.Length, out zipGenericExtraField))
{
zipGenericExtraFields.Add(zipGenericExtraField);
}
}
return(zipGenericExtraFields);
}
